Related papers: A Helioscope for Gravitationally Bound Millicharge…
The likelihood of detecting individual discrete sources of cosmic rays depends on the mean separation between sources. The analysis here derives the minimum separation that makes it likely that the closest source is detectable. For…
Diffuse $\gamma$-ray emission is the most prominent observable signature of celestial cosmic-ray interactions at high energies. While already being investigated at GeV energies over several decades, assessments of diffuse $\gamma$-ray…
Observations of our Galaxy at very-high and ultra-high photon energies have revealed a rich population of sources, many of which have significant angular extension and/or are positionally coincident with energetic pulsars. We assessed…
We propose a novel direct detection concept to search for dark matter with 100~keV to 100~MeV masses. Such dark matter can scatter off molecules in a gas and transfer an $\mathcal{O}(1)$ fraction of its kinetic energy to excite a…
Investigating the properties of magnetic flux emergence is one of the most important problems of solar physics. In this study we present a newly developed deep-focus time-distance measurement scheme which is able to detect strong emerging…
Gravitational microlensing is a new technique that allows low-mass exoplanets to be detected at large distances of ~7kpc. This paper briefly outlines the principles of the method and describes the observational techniques. It shows that…
We study flare processes in the lower solar atmosphere using observational data for a M1-class flare of June 12, 2014, obtained by New Solar Telescope (NST/BBSO) and Helioseismic Magnetic Imager (HMI/SDO). The main goal is to understand…
Electron beams accelerated in solar flares and escaping from the Sun along open magnetic field lines can trigger intense radio emissions known as type III solar radio bursts. Utilizing observations by Parker Solar Probe (PSP), STEREO-A…
The measurements of the possible gravitational microlensing events are analysed with a simple yet accurate disc--halo model of the Milky Way Galaxy. This comprises a luminous exponential disc embedded in a flattened dark matter halo with…
Two coherent radio emission mechanisms operate in stellar coronae: plasma emission and cyclotron emission. They directly probe the electron density and magnetic field strength respectively. Most stellar radio detections have been made at…
Context. Tracing wave activity from the photosphere to the corona has important implications for coronal heating and prediction of the solar wind. Despite extensive theory and simulations, the detection of waves in realistic MHD simulations…
Solar macrospicules are beam-like cool plasma ejections of size in-between spicules and coronal jets, which can elucidate potential connections between plasma jetting activity at different scales. With high-resolution observations from the…
Stellar flares have been extensively studied in soft X-rays (SXR) by basically every X-ray mission. Hard X-ray (HXR) emission from stellar superflares, however, have only been detected from a handful of objects over the past years. One very…
A particular open problem in cosmology is whether dark matter on small scales is clumpy, forming gravitationally-bound halos distributed within the Galaxy. The practical difficulties inherent in testing this hypothesis stem from the fact…
Previous work has shown that optomechanical force sensing can be used for efficient detection of ultralight (sub-eV) dark matter candidates. We propose to extend the reach of this method to the search for ultralight dark matter in…
We consider nuclear gamma decays and $\gamma$-emitting reactions that can be an efficient source of hypothetical millicharged particles ($\chi$). In particular, we revisit the production of millicharged particles in nuclear reactor…
We describe detection methods for extensions of gravitational wave searches to sub-solar mass compact binaries. Sub-solar mass searches were previously carried out using Initial LIGO, and Advanced LIGO boasts a detection volume…
While it is possible to estimate the dark matter density at the Sun distance from the galactic center, this does not give information on actual dark matter density in the Solar system. There can be considerable local enhancement of dark…
Gravitational positivity bounds provide consistency conditions for effective field theories with gravity. They turn out to be phenomenologically useful by providing lower bounds in parameters of new physics beyond the Standard Models (BSM).…
The aim of this study is to generate maps of the hard X-ray emission produced by energetic electrons in a solar flare and compare them with observations. The ultimate goal is to test the viability of the combined MHD/test-particle approach…